• Bulletin of the Korean Chemical Society
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• v.31 no.1
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• pp.151-156
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• 2010

In this paper, we characterized bimetallic Pt-Ru/C alloy catalysts having four different compositions and compared the catalytic activities of the prepared alloys for CO oxidation. ICP-AES, EDS, XRD, TEM, and XAS were used to investigate the composition, degree of alloying, particle size, and electronic structure of the prepared Pt-Ru/C catalysts. Those results indicated the synthesis of the alloy catalysts with intended composition and uniform size. The electrochemical study of the characterized alloys showed higher catalytic activity for CO oxidation than that of the commercial Pt/C (E-TEK, Inc., 20 wt %) catalyst. Especially, it was shown that the alloy catalyst with Ru composition of 50 atomic % gave the highest catalytic activity for CO oxidation.

• Journal of the Korean Society of Tobacco Science
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• v.27 no.1 s.53
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• pp.40-50
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• 2005

The influence of tobacco additives on the composition of the combustion products in mainstream smoke is discussed. The effect of additives on the chemical composition of smoke have been further evaluated in order to discover additives that would alter the chemical composition of smoke. Tobacco was uniformly treated at a 1-5$\%$ level with 8 classes of additives. Group M treated with alkali metal salt and group S, F, O give lower tar, nicotine and CO values than the control. Group AN treated with natural antioxidant gives higher tar and CO values than the control. The increases are most probably due to the high transfer rate of the ingredients to smoke. M3 and P1 reduced above the $50\%$ of TSNA from the smoke. M4 and P1 reduced above the $50\%$ of HCN from the smoke. These results suggest that tobacco additives alter pyrolysis or combustion product distribution and provide fundamental data to lead the development of a RRP(reduced risk product).

• Journal of Microbiology and Biotechnology
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• v.27 no.5
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• pp.939-942
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• 2017

The cellular composition and metabolic compounds of Leuconostoc mesenteroides ATCC 8293 were analyzed after cultivation in an anaerobic chemostat. The macromolecular composition was 24.4% polysaccharide, 29.7% protein, 7.9% lipid, 2.9% DNA, and 7.4% RNA. Its amino acid composition included large amounts of lysine, glutamic acid, alanine, and leucine. Elements were in the order of C > O > N > H > S. The metabolites in chemostat culture were lactic acid (73.34 mM), acetic acid (7.69 mM), and mannitol (9.93 mM). These data provide a first view of the cellular composition of L. mesenteroides for use in metabolic flux analysis.

• Journal of Conservation Science
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• v.31 no.3
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• pp.319-330
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• 2015

This study attempted to review the chemical composition of 25 samples of Sangpyeongtongbo having different manufacturing place and period, and then to find the manufacturing method. As a result of chemical composition analysis of Sangpyeongtongbo, main components include Cu, Zn and Pb, and some samples contained Sn and Fe. But, the chemical composition of each Sangpyeongtongbo varied with big differences. When the main content change was examined, Cu and Sn became decreased at the later period, and Zn and Pb had higher contents. The difference in the ingredient content had close relation for the profit of Sangpyeongtongbo. When refined microstructure was observed, 25 kinds of Sangpyeongtongbo had developed different types of microstructure such as dendrite, large grain and grain refinement. But, 25 kinds of Sangpyeongtongbo had no heat treatment processing. And, the types of microstructure were difference, which seems because different microstructure was developed due to the difference of Sn and Fe and cooling speed in Sangpyeongtongbo.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1593-1604
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• 2016

Recently, bacterial quorum quenching (QQ) has been proven to have potential as an innovative approach for biofouling control in membrane bioreactors (MBRs) for advanced wastewater treatment. Although information regarding the microbial community is crucial for the development of QQ strategies, little information exists on the microbial ecology in QQ-MBRs. In this study, the microbial communities of biofilm were investigated in relation to the effect of QQ on anoxic/oxic MBRs. Two laboratory-scale MBRs were operated with and without QQ-beads (QQ-bacteria entrapped in beads). The transmembrane pressure increase in the QQ-MBRs was delayed by approximately 100-110% compared with conventional- and vacant-MBRs (beads without QQ-bacteria) at 45 kPa. In terms of the microbial community, QQ gradually favored the development of a diverse and even community. QQ had an effect on both the bacterial composition and change rate of the bacterial composition. Proteobacteria and Bacteroidetes were the most dominant phyla in the biofilm, and the average relative composition of Proteobacteria was low in the QQ-MBR. Thiothrix sp. was the dominant bacterium in the biofilm. The relative composition of Thiothrix sp. was low in the QQ-MBR. These findings provide useful information that can inform the development of a new QQ strategy.

• Fashion & Textile Research Journal
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• v.15 no.3
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• pp.430-436
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• 2013

The purpose of this study investigates the effects of electron beam(EB) irradiation on the chemical and morphological properties of Hansan ramie fiber. Hansan ramie fibers were irradiated with electron beam doses of 0, 1, 3, 5 and 10kGy. The effect of electron beam irradiation on the chemical components of fibers as well as the surface chemical and morphological properties were investigated using chemical component analysis methods based on TAPPI standards, XPS, and SEM. The results indicate that the surface layers can be removed under suitable EB irradiation doses. Alcohol-benzene extraction and lignin content increases gradually with an increase in EB irradiation and reaching a maximum at an EB dose of 3kGy, and decreases at 10kGy. The surface chemical changes measured by XPS corresponded to the chemical composition analysis results. The C1 peak and the O/C ratio decreased with the removal of the multi-layer and primary layer by EB irradiation. The SEM images show the inter-fibrillar structure etched by EB irradiation up to 5kGy. At 10kGy, the surface structure of the ramie fiber shows highly aligned and distinctive striations in a longitudinal direction. The removal of these exterior layers of the fiber was confirmed by changes in surface morphology as observed in SEM images.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.1
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• pp.47-51
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• 2004

Ceramide III was prepared by the cultivation of Saccharomyces cerevisiae. Ceramide III was partitioned from the cell extracts by solvent extraction and analyzed by Normal Phase High Performance Liquid Chromatography (NP-HPLC) using Evaporative Light Scattering Detector (ELSD). We experimentally determined the mobile phase composition to separate ceramide III with NP-HPLC. Three binary mobile phases of n-hexane/ethanol, n-hexane/lsoprophyl Alcohol(IPA) and n-hexane/n-butanol and one ternary mobile phase of n-hexane/IPA/methanol were demonstrated. For the binary mobile phase of n-hexane/ethanol, the first mobile phase composition, 95/5(v/v), was step-increased to 72/23(v/v) at 3 min. In the binary mobile phase, the retention time of ceramide III was 7.87min, while it was 4.11 min respectively in the ternary system, where the mobile phase composition of n-hexane/IPA/methanol, 85/7/8(v/v/v), was step-increased to 75/10/15(v/v/v) at 3 min. However, in the ternary mobile phase, the more peak area of ceramide III was observed.

• Journal of Environmental Science International
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• v.26 no.12
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• pp.1333-1339
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• 2017

Coal-fired power plants emit various Particulate Matter(PM) at coal storage pile and ash landfill as well as the stack, and affect the surrounding environment. Field Emission Scanning Electron Microscopy and Energy Dispersive X-ray analyzer(FE-SEM/EDX) were used to develop identification factor and the physico-chemical analysis of PM emitted from a power plant. In this study, three samples of pulverized coal, bottom ash, and fly ash were analyzed. The pulverized coal was spherical particles in shape and the chemical composition of C-O-Si-Al and C/Si and C/Al ratios were 200~300 on average. The bottom ash was spherical or non-spherical particles in shape, chemical composition was O-C-Si-Al-Fe-Ca and C/Si and C/Al ratios were $4.3{\pm}4.6$ and $8.8{\pm}10.0$. The fly ash was spherical particles in shape, chemical composition was O-Si-Ai-C-Fe-Ca and C/Si and C/Al ratios were $0.5{\pm}0.2$ and $0.8{\pm}0.5$.

• Journal of the Korean Wood Science and Technology
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• v.28 no.4
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• pp.10-16
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• 2000

Two wood decay ascomycetes fungi identified as Hypoxylon mammatum and H. truncatum were isolated from backyard of Korea Research Institute of Chemical Technology (KRICT) in Korea. Hypoxylon truncatum is newly recorded as a wood degrader in Korea. Unusual germination mechanisms of ascospores in H. mammatum and H. truncatum are described and illustrated. The differences between two species were noticed on the process of germ tube formation. In the process of germ tube formation, the fast movement to pigmented ascospores activated from their perispores was termed as spore eclosion that was only found in H. mammatum. This sophisticated recognition mechanism indicated the existence of specific eclosion and germ tube formation due to the composition of cell wall layers and their preferable host derive, based on examined two species under a genus. The observation on present study postulates different composition of wall layers of ascospore and different nutrient composition for germination.

• Journal of the Korean Wood Science and Technology
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• v.25 no.3
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• pp.24-28
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• 1997

As a way to revive the traditional technology of Korean golden varnish(Hwangchill), the exudates of D. morbifera, this study was carried out at first to investigate the anatomical characteristics and the chemical composition of D. morbifera stems and their exudates. Trees of more than 20 years old were harvested at Wando and Jejudo islands in the southwestern part of Korean peninsula during different physiological seasons of winter, spring, and summer, The results obtained are as follows: 1. In the anatomical aspect of wood, Hwangchil woods is ring-porous wood, has alternate inter-vessel pittings and horizontal intercellular canal in xylem. 2. In the chemical aspect of wood and bark, the general compositions appeared hot to differ from those of other hardwoods, and ash and alcohol-benzene extractives showed little increase with the increase of atmospheric temperature of harvesting season. 3. In the solvent-sequential extraction of bark, wood and exudate, the exudates was extracted up to 80% by ether, but the bark and wood contained a very small amount of ether extractives, about 2% in the bark and 0.5% in the xylem.